The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 05, 2002
Filed:
Mar. 30, 1998
Chi Shih Chang, Austin, TX (US);
William T. Chen, Endicott, NY (US);
Ajit Trivedi, Endicott, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
The present invention describes a method and apparatus for packaging a flip chip by matching the z-direction CTE of the IC solder joint with the z-direction CTE of the encapsulant. Consideration of the z-direction CTE's is important when determining the volumetric CTE of the encapsulant. This invention first requires a determination of the z-direction CTE of the IC solder joint and a determination of the z-direction CTE of the encapsulant. The invention next matches the z-direction CTE of the IC solder joint to the z-direction CTE of the encapsulant. The matching of the two z-direction CTE's reduces the z-direction tensile or compression stresses on the IC solder joint and the encapsulant.